Phat Beat increase VU meter sesitivity


#1

Is there a way to increase the VU meter sensitivity so it peaks at lower volume levels? The sound is way to loud if I turn it up enough to get a good indication on the VU meter. Most of the time only the bottom two LED’s flicker. I didn’t see anything relevant in the alsa config file for the pHat Beat.


#2

It’s in my TODO list- actually I’m completely re-working how the VU works so that the front-end (the bit which actually displays the VU data on your HAT/pHAT etc) is entirely Python, making it easier for people to tweak to their needs.

See: https://github.com/pimoroni/pivumeter/tree/devel/python_server

Or, in your case, https://github.com/pimoroni/pivumeter/blob/devel/python_server/examples/phatbeat-server.py

The trouble is, however, that the front-end, and even ALSA itself (where the plugin to grab the VU data is inserted) have, as far as I’m aware, absolutely no knowledge of what the current volume level is. I plan to rectify that by doing a rather clunky call out to amixer like so:

    def get_volume(self):
        actual_volume = subprocess.check_output("amixer get 'PCM' | awk '$0~/%/{print $4}' | tr -d '[]%'", shell=True)
        if version_info[0] >= 3:
            return actual_volume.strip().decode('utf-8')
        else:
            return actual_volume.strip()

#3

I was hoping for a reply along those lines. I saw the older threads on the same subject, with the its being looked at comments. It’s a nice bit of kit and IMHO, could be a lot better with some tweaking. I just don’t have the skills to tweak it myself. Thanks for the reply and the links, will definitely have a look see.


#4

As long as you’ve got the skills to join the crowd of people nagging me to get it done, that should move it along nicely ;)

Still! I wholeheartedly encourage you trying to get the linked dev branch of PiVUMeter up and running on your own ;) it may end in failure, but it will certainly result in learning.


#5

I have next to no Linux skills. Some Python skills, but that was mostly from learn by example. I will research it some and maybe give it a try. I have a spare Micro SD card to play around with and not mess up what’s working now.


#6

Has there been any progress on this?
I have just put together a phat beat and all is well except for the issue of the VU meter not really displaying anything unless the volume is cranked way up.

As it is it’s a nice sound card for the Pi Zero but the VU meter doesn’t really work.


#7

I put it on the back burner and then forgot all about it. ops.